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  Subjects -> AERONAUTICS AND SPACE FLIGHT (Total: 124 journals)
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IEEE Journal on Miniaturization for Air and Space Systems
Number of Followers: 4  
 
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Online) 2576-3164
Published by IEEE Homepage  [228 journals]
  • The Journal of Miniaturized Air and Space Systems

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      Abstract: Presents a listing of the editorial board, board of governors, current staff, committee members, and/or society editors for this issue of the publication.
      PubDate: Dec. 2022
      Issue No: Vol. 3, No. 4 (2022)
       
  • Small Satellite Orbit Determination Using Single Pass Doppler Measurements

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      Authors: Alexander A. Spiridonov;Vladimir A. Saetchnikov;Dmitrii V. Ushakov;Vladimir E. Cherny;Alexey G. Kezik;
      Pages: 162 - 170
      Abstract: The Doppler measurements of the telemetry radio signals nanosatellite CubeBel-1 for a single pass over the Belarusian State University ground station were carried out. Two methods for orbit determination of a small satellite (SS) are considered. The first method is based on the SGP4 model and requires additional information from the North American Aerospace Defense Command (NORAD) two-line elements (TLE) catalog of the satellite orbital parameters. An unknown SS is identified using the NORAD TLE catalog based on a probabilistic estimation of the elevation angle and the Doppler frequency shift of receiving telemetry signals. The first method was allowed to determine the nanosatellite CubeBel-1 unambiguously. The second method is based on processing experimental measurements of the Doppler frequency of the telemetry radio signals and the Keplerian circular motion model for SS. It does not require additional information from the NORAD database of satellite orbital parameters. The second method was allowed only to calculate the average state vector unknown satellite. Finally, the corrected state vector in the geocentric inertial coordinate system was obtained based on the differential correction method.
      PubDate: Dec. 2022
      Issue No: Vol. 3, No. 4 (2022)
       
  • A Feasibility Study for Signal-in-Space Design for LEO-PNT Solutions With
           Miniaturized Satellites

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      Authors: Ruben Morales Ferre;Jaan Praks;Gonzalo Seco-Granados;Elena Simona Lohan;
      Pages: 171 - 183
      Abstract: The global navigation satellite systems (GNSSs) are increasingly suffering from interferences, such as coming from jammers and spoofers, and their performance is still modest in challenging urban and indoor scenarios. Therefore, there are efforts worldwide to develop complementary positioning, navigation, and timing (PNT) solutions. One such complementary method under current research is the so-called LEO-PNT, namely, PNT solutions based on low-Earth orbit (LEO) satellites, and in particular on small-sized or miniaturized satellites. Such satellites have low-to-moderate costs of building, launching, and maintenance. Several challenges are to be overcome when designing a new LEO-PNT solution, concerning all three satellite segments: 1) the signal-in-space (SIS) or space segment; 2) the ground segment; and 3) the user/receiver segment. This article presents a survey of the SIS design challenges under the inherent constraints of wireless-channel propagation impairments as well as some design recommendations for SIS features. We address different constellation types, achievable coverage limits, and geometric dilution of precision (GDOP) bounds, as well as achievable carrier-to-noise ratios (CNRs) under a realistic wireless channel model, based on a MATLAB Quadriga simulator. We also discuss several optimization criteria regarding LEO-PNT SIS design, by taking into account the tradeoff between a low cost/low number of satellites in orbit on the one hand, and a sufficient coverage and good CNR for PNT purposes on the other hand.
      PubDate: Dec. 2022
      Issue No: Vol. 3, No. 4 (2022)
       
  • Flight Software Development for a CubeSat Application

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      Authors: Koffi V. C. K. de Souza;Yassine Bouslimani;Mohsen Ghribi;
      Pages: 184 - 196
      Abstract: This article presents a development of a CubeSat mission software running on an STM32-based on-board computer (OBC). This was conducted under the Canadian CubeSat Project, initiated by the Canadian Space Agency in 2018 to support the development of 15 CubeSats across Canada. The proposed mission software has a multilayered architecture and is divided into five layers from a low layer dedicated to the peripherals to the top layer dedicated to the Mission Applications. The CubeSat protocol (CSP) is used at the communication layer for easing connectivity between subsystems and to communicate with the ground segment. The mission software running on the OBC is built to meet many requirements defined for this satellite, such as version control, classifications, margins, etc. The CubeSat will be able to accomplish two scientific missions related to the study of space weather once the satellite is put into orbit from the International Space Station. An overview of the software running on the OBC is presented, written in C Language, and includes the implementation of the CSP. FreeRTOS used as an operating system for the OBC is also presented. A Command Line Interface was designed for testing purposes to ensure software efficiency and some results are discussed in this article. The flight software consists of three main tasks and subtasks. Of the 1024 kB of flash memory, only 240 kB was used which represents less than 20% of the total memory. The CPU load is 34% for normal, manual, and maintenance modes and 16% for failure modes.
      PubDate: Dec. 2022
      Issue No: Vol. 3, No. 4 (2022)
       
  • Polarimetric SAR Ship Detection Based on Scattering Characteristics

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      Authors: Sheng Gao;Hongli Liu;
      Pages: 197 - 203
      Abstract: A synthetic aperture radar is crucial for detecting ships. In this study, to improve the detection capability of weakly scattering targets and reduce false alarms, a detector $F_{vh}$ based on the scattering characteristics of ships is proposed after an in-depth study of the differences between ship and sea surface scattering mechanisms. The volume scattering mechanism and the helix scattering mechanism are fused, and the volume scattering power is used to describe the scattering structure on the ship, and the helix scattering power is used to increase the difference between the ship and the sea surface. We test on 4 GF-3 fully polarized synthetic aperture radar data. The experimental results show that $F_{vh}$ has improved detection capability and can successfully minimize false alarm generation.
      PubDate: Dec. 2022
      Issue No: Vol. 3, No. 4 (2022)
       
  • Phase Estimation for Distributed Scatterers by Alternating Projection

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      Authors: Ruya Xiao;Xiufeng He;Zhuang Gao;Fengyu Yao;
      Pages: 204 - 210
      Abstract: Decorrelation is a major obstacle to the application of multitemporal interferometric synthetic aperture radar (InSAR) in areas with low coherence. Distributed scatterers (DSs) with similar backscattering in the spatial neighborhood are the key to improving the observational density and accuracy of deformation estimation in fast decorrelation regions. Phase series estimation from all possible interferograms is expected to improve the signal-to-noise ratio (SNR) and further enhance the sensitivity of deformation measurement. The coherence bias and the efficiency of the phase estimation raise concerns. In this article, we propose a computationally attractive algorithm for the interferometric phase estimation, namely alternating projection (AP), which is a combination of the alternating maximization and the projection matrix decomposition methods. The homogenous pixel selection and coherence estimation bias correction are conducted by the FaSHPS algorithm and DSIpro software toolbox. Results of simulations and real SAR data show that the proposed AP method could reconstruct credible phase series comparable to the quasi-Newton optimization algorithm [Broyden–Fletcher–Goldfarb–Shanno (BFGS)] while having three times the efficiency gain.
      PubDate: Dec. 2022
      Issue No: Vol. 3, No. 4 (2022)
       
  • An Optimized Plane-Change Solution for Microsatellite Formation Flying

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      Authors: Shu Ting Goh;Samuel Y. W. Low;Kay-Soon Low;Eng Kee Poh;
      Pages: 211 - 220
      Abstract: The cross-track baseline requirement in a satellite formation flying mission requires an orbital plane-change maneuver during the acquisition phase. While the optimization of orbital plane-change maneuver has been well studied, the constraints of the propulsion system, such as the power limitation, battery charging cycle, and finite thrust durations, are often neglected. In addition, the self-pressurized chemical propulsion system used in this satellite mission experiences a performance degradation effect over prolonged use in terms of specific impulse and thrust force. To overcome these constraints on the orbital plane-change maneuver process, this article proposes an optimized algorithm by minimizing Edelbaum’s equation using a selective constrained ensemble Kalman filter that includes propulsion’s performance variation and firing duration constraints. Monte Carlo simulations have been conducted to benchmark the proposed method against the theoretical impulsive thrusts in terms of $Delta V$ , and the commonly adopted natural precession-based plane-change method in terms of the total time taken. Results from the simulation have shown that the required $Delta V$ of this proposed method is similar to the theoretical impulsive burn method. In addition, it requires a 75% shorter time than the natural precession method in achieving the desired plane change and is 36% more fuel efficient than the direct firing method. Furthermore, this study has verified that this algorithm can be directly integrated with the existing formation control algorithm.
      PubDate: Dec. 2022
      Issue No: Vol. 3, No. 4 (2022)
       
  • Enabling Science With CubeSats—Trends and Prospects

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      Authors: Ratul De;Mahesh P. Abegaonkar;Ananjan Basu;
      Pages: 221 - 231
      Abstract: The emergence of CubeSats/SmallSats began a miniaturization revolution in the satellite domain nearly 20 years ago. Only a few people could have predicted their capabilities at the time and, today, these small satellites are changing the world in a completely different way. They have established themselves as a viable science platform. These small satellites are the best candidates for high-risk science missions. CubeSat constellations or swarm missions will usher in a new era of space exploration by providing multipoint measurements. This article provides a brief overview of CubeSat as a science platform, as well as their potential and challenges for future scientific missions. It also provides an overview of the existing CubeSat systems, with a focus on communication subsystems, particularly antennas and RF front ends. The proper utilization of CubeSat space with highly efficient integrated or shared components is a trending research area these days, and this article will provide a glimpse of that. The system requirements for future missions are also discussed, which will serve as a guide for CubeSat system developers.
      PubDate: Dec. 2022
      Issue No: Vol. 3, No. 4 (2022)
       
  • Multiagent Collaboration for Emergency Evacuation Using Reinforcement
           Learning for Transportation Systems

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      Authors: Yupeng Yang;Jiahao Yu;Dahai Liu;Sang-A Lee;Sirish Namilae;Sabique Islam;Huaxing Gou;Hyoshin Park;Houbing Song;
      Pages: 232 - 241
      Abstract: Reinforcement learning (RL) has been widely used in intelligent transportation systems. Especially under emergent situations, RL can explore unsafe environments and make optimal decisions to guide the evacuation process for human beings. Multiagent collaboration allows agents to communicate and interact for a more efficient exploration and evacuation process, especially when the uncertainty level is high. In this study, robot agents or drones were used to explore and evacuate from environments with different levels of complexity and with or without collaboration using the RL $Q$ -learning algorithm. The multiagent collaboration method was found to perform better than the single-agent exploration concerning evacuation time, death counts, and reward. These results as well as future research directions are discussed in the context of emerging literature.
      PubDate: Dec. 2022
      Issue No: Vol. 3, No. 4 (2022)
       
  • Optical Design and Analysis of Theia: A Scientific-Grade Multispectral
           Imager for Nanosatellites

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      Authors: Joosep Kivastik;Hans Hubert Sams;Silvar Muru;Hendrik Ehrpais;Tõnis Eenmäe;Joel Kuusk;Andris Slavinskis;Mihkel Pajusalu;
      Pages: 242 - 248
      Abstract: This article describes the optical design and analysis of Theia: a miniature, scientific-grade, multispectral Earth observation imager for nanosatellites that can be used for quantitative remote sensing. The instrument is designed to take images with a 5% radiometric accuracy throughout its three-year lifetime. The sustained accuracy is achieved with a post-launch calibration module. The instrument can capture frames at a 33-m ground sampling distance at an orbit height of 650 km. The design can take diffraction-limited images with a modulation transfer function of at least 0.13 at the sensor’s Nyquist frequency, which is comparable with Sentinel-2’s MultiSpectral Instrument. The instrument works in two user-defined bands, fits inside one CubeSat unit, and weighs 600 g. The successful analysis of the system is presented, including optical performance, radiometric, stray light, and tolerance analyses.
      PubDate: Dec. 2022
      Issue No: Vol. 3, No. 4 (2022)
       
  • Performance Evaluation of Data Enhancement Methods in SAR Ship Detection

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      Authors: Chi Zhang;Xi Zhang;Jie Zhang;Gui Gao;Jingke Zhang;Genwang Liu;Yongjun Jia;Xiaochen Wang;Yi Zhang;Yongshou Dai;
      Pages: 249 - 255
      Abstract: In recent years, researchers have started to apply neural networks to ship detection of synthetic aperture radar (SAR). However, SAR images are difficult to acquire and interpret manually. Sufficient training samples cannot be obtained, which limits the performance of ship detection. Therefore, data enhancement has become an active means to handle the issue of insufficient samples. To evaluate the performance of diverse data enhancement methods, a variety of data enhancement methods is used to expand the ship samples in the SAR ship detection dataset, including rotation, shift, mirror, brightening, etc. Moreover, we used the combination of diverse data enhancement methods for experiments. Experiments were performed using the SSDD dataset. Based on the experimental results, we analyze the characteristics of diverse data enhancement methods.
      PubDate: Dec. 2022
      Issue No: Vol. 3, No. 4 (2022)
       
  • Impacts of the COVID-19 Epidemic on Ship Activity in Dongying Port Waters

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      Authors: Yanan Guan;Jie Zhang;Xi Zhang;Gui Gao;Junmin Meng;Genwang Liu;Chenghui Cao;Xiaochen Wang;
      Pages: 256 - 263
      Abstract: The automatic identification system (AIS) provides detailed information about vessel movement that has gained wide application in areas such as ship behavior analysis over the past decade. Based on the AIS data in January and February of the lunar calendar in 2019 and 2020, this study analyzed the number and size of ships, the spatial distribution characteristics, such as ship position and density, ship speed, as well as the temporal characteristics of daily and monthly changes of ship flow, and then evaluated the impact of the COVID-19 epidemic on ship activities in Dongying Port waters. The results show that the number of tankers declined to a lesser extent compared to fishing and cargo ships after the outbreak of the COVID-19 epidemic. Because berthing activities would require extra operating time due to the epidemic, ships may require longer turnaround times. In general, tankers in Dongying Port waters were less affected by the epidemic than cargo and fishing ships.
      PubDate: Dec. 2022
      Issue No: Vol. 3, No. 4 (2022)
       
  • Simultaneous Polarization Measurement and High-Resolution Imaging
           Algorithm Inspired by Bat Sound Waveform

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      Authors: Biao Shen;Tao Liu;Weijian Liu;Gui Gao;
      Pages: 264 - 275
      Abstract: The acquisition and utilization of polarization information is an open topic because polarization plays a significant role in many fields, such as radar target detection, classification, recognition, synthetic aperture radar (SAR) imaging, anti-jamming, etc. Inspired by the bat sound waveform and combined with the properties of the stepped linear frequency modulation (SLFM) signal, in this article, a novel polarization waveform, namely, simultaneous SLFM (SSLFM), which can be used for small airborne and spaceborne polarimetric SAR (PolSAR) platform, is proposed. Moreover, a method based on the SSLFM signal is proposed to realize simultaneous polarization measurement and double high-resolution imaging. It is demonstrated that the method can better make use of the polarization information of echoes and obtain a better imaging effect. The feasibility of the proposed method is verified by simulation experiments.
      PubDate: Dec. 2022
      Issue No: Vol. 3, No. 4 (2022)
       
  • Impact and Correction of Sea Ice, Snow, and Seawater Density on Arctic
           Sea-Ice Thickness Retrieval From Ku-Band SAR Altimeters

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      Authors: Xi Zhang;Quanfang Zhao;Gui Gao;Jie Zhang;Meng Bao;Junmin Meng;
      Pages: 276 - 283
      Abstract: Satellite radar altimeters (RAs) can measure sea-ice thickness on a large scale. According to the assumption of isostatic equilibrium, knowing the density of water, snow, and ice is crucial to estimating the thickness of sea ice from altimeters. Therefore, using inaccurate density values to estimate sea-ice thickness from RAs will lead to unreliable results. This article proposes a method to evaluate and correct density ( $rho $ ) ratios, $rho _{w}/{(}rho _{w}-rho _{i}{)}$ and $rho _{s}/{(}rho _{w}-rho _{i}{)}$ , where subscripts ${i}$ , ${w}$ , and ${s}$ represent sea ice, water, and snow, respectively, by using sea ice freeboard of CryoSat-2 (CS-2) and Sentinel-3A (S3), Operational IceBridge ice thickness, and modified climatological snow depth data. In addition to comparing the calculated density ratio (DR) with the DR commonly used in the previous studies, we also investigate how input density parameters affect the accuracy of freeboard-to-thickness conversion of the satellite RA. Our results indicate that the $rho _{i}$ of first-year ice (FYI) region used by the ESA sea ice climate change initiative product (ESA SICCI) is generally large, whereas $rho _{s}$ is significantly small. For a more accurate inversion of Arctic sea-ice thickness, $rho _{w}/{(}rho _{w}-rho _{i}{)} = 9.01$ and $rho _{s}/{(}rho _{w}-rho _{i}{)} = 3.52$ can be used for FYI, and $rho _{w}/{(}rho _{w}-rho _{i}{)} = 7.20$ and $rho _{s}/(rho _{w}-rho _{i}) =2.30$ can be used for multiyear ice (MYI) region. Because $rho _{w}$ is relatively stable and easy to observe, the proposed method also can be used to invert sea ice density $rho _{i}$ and snow layer density $rho _{s}$ from estimated DRs.
      PubDate: Dec. 2022
      Issue No: Vol. 3, No. 4 (2022)
       
  • Modeling and Parameter Representation of Sea Clutter Amplitude at
           Different Grazing Angles

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      Authors: Chenghui Cao;Jie Zhang;Xi Zhang;Gui Gao;Yi Zhang;Junmin Meng;Genwang Liu;Zhenhua Zhang;Qianqian Han;Yongjun Jia;Xiaochen Wang;
      Pages: 284 - 293
      Abstract: Study on sea clutter is highly important in the field of maritime surveillance. The physical mechanism of sea clutter is complex and there are many influencing factors, among which the grazing angle is one of the most important. To address the problem of determining the suitability of models of sea clutter, this study performed a comprehensive goodness-of-fit (GoF) analysis of six sea clutter models using five methods at different grazing angles, bands, and azimuths. Furthermore, to improve the description of sea clutter amplitude, we proposed a new parameter representation method. The proposed new parameters can be used to analyze the characteristics of sea clutter amplitude and evaluate the GoF of sea clutter models at different grazing angles. Experimental data were obtained using airborne radar at a low grazing angle and spaceborne synthetic-aperture radar at medium–high grazing angles. The results indicate that the characteristics of sea clutter amplitude are various with different azimuths and grazing angles, whereas there are no significant differences between the ${X}$ and ${C}$ bands. In detail, ${K}$ distribution and generalized gamma distribution ( $text{G}Gamma text{D}$ ) are recommended in side-looking, while ${G}^{0}$ and ${K}$ distributions are recommended in forward-looking at low grazing angle; at medium–high grazing angle, ${K}$ , $text{G}Gamma text{D-$ , and Weibull distributions are recommended for the ${X}$ band, while ${K}$ and ${G} ^{0}$ distributions are recommended for the ${C}$ band. Compared with mean-square error, Kullback–Leibler, Bhattacharyya distance, threshold error, and graphical GoF methods, the proposed method was demonstrated to be simple and efficient in evaluating the GoF of sea clutter models.
      PubDate: Dec. 2022
      Issue No: Vol. 3, No. 4 (2022)
       
  • A CLEAN-Based Synthetic Aperture Passive Localization Algorithm for
           Multiple Signal Sources

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      Authors: Yuqi Wang;Wenlong Dong;Guang-Cai Sun;Zijing Zhang;Mengdao Xing;Xiaoniu Yang;
      Pages: 294 - 301
      Abstract: In passive localization, the received signal may come from multiple signal sources with different modulations. The modulations are usually resolved by high-order spectrum (HOS) processing. However, the processing causes multiple intersignal cross terms, resulting in a degradation of localization performance. To resolve the problem, this article proposes a CLEAN-based synthetic aperture passive positioning algorithm for multiple signal sources. The main idea is to locate the same modulated signal by focusing and then filtering out the located signal. Signals with the same modulation are located through the synthetic aperture passive localization method. Then, the located signals are removed and the remaining signals are recovered through inverse focusing. The multiple signals are focused, extracted, and separated according to the modulation. The effect of cross terms and multiplicative noise in the HOS is dramatically reduced. The simulation experiments show that the proposed algorithm can effectively improve localization accuracy.
      PubDate: Dec. 2022
      Issue No: Vol. 3, No. 4 (2022)
       
  • 2022 Index IEEE Journal on Miniaturization for Air and Space Systems Vol.
           3

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      Pages: 302 - 311
      Abstract: Presents the 2022 author/subject index for this issue of the publication.
      PubDate: Dec. 2022
      Issue No: Vol. 3, No. 4 (2022)
       
 
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